Honolulu is opening its food scrap composting program to every household with a green cart starting October 1, a small win for residents who want to cut waste at no extra cost.

• Anyone with a green compost cart can start tossing food scraps in it — same pickup days, no added fee.
• The pilot drew 50% participation, well above what similar programs get on the mainland, which is why the city is going islandwide.
• Food goes in loose, buried under yard waste; baking soda and coffee grounds keep the smell down, and freezing scraps until pickup night helps too.
• Meat, bones, leftovers and produce are all fine — but no plastic bags, no compostable containers, no paper plates, no liquids, no pet waste.

Outlook: The city wants participation to climb well past half of households now that the program covers the whole island.